WATER TREATMENT CHEMICALS | Forum

Ethylenediaminetetraacetic acid (EDTA) has a proven record of aiding in
the protection of water treatment pipes and equipment. Bell Chem, the
water treatment chemical supplier you can trust in Central Florida,
carries this HEDP for its ability to effectively sequester metals within pipes.

Deposition is a fact of life for water treatment plants. Water
purity determines the likelihood of deposits left within the boilers and
other portions of the feed lines. When feedwater contains even the
slightest amount of impurity, the possibility of buildup along any metal
surface is almost guaranteed.

Contaminants common in feedwater include metals (magnesium, copper,
iron, aluminum), nonmetals (calcium and silica), silt, and oil. These
categories are identified as either scale or sludge. Scale is formed by
salt crystals that adhere to surfaces while sludge precipitates outside
the water treatment system and is transported to the metal surface of
the treatment system by means of incoming water.

Scale formations are soluble until they concentrate due to the high
heat transfer rates that drive evaporation. Because the crystalline
structure of scale is homogeneous, different areas of scale may have
completely different chemical compositions and require varied methods of
removal. Both metals (magnesium, aluminum, and iron) and nonmetals
(calcium, silica, and occasionally sodium) can create scale. Scale forms
extremely slowly, which causes the buildup to be hard, dense, and well
defined, giving scale the ability to withstand most mechanical and
chemical cleaning.

Sludge deposits may also prove to be dense, hard, and difficult to
remove, especially after exposure to extreme heat levels, which bakes
the sludge onto the surface of the water treatment equipment. Baked
sludge is similar to scale in its tenaciousness.

Once either sludge or scale forms inside a facility, the chemical
contaminants attract like chemicals. This results in larger and larger
patches of affected metal. These accumulations inside pipes can
significantly increase water pressure because the diameter of the pipes
diminishes, causing overheating and, especially with salts, corrosion.
Removing scale and sludge results in facility downtime.